With the increasing widespread application of wireless technologies, a multiple-input multiple-output (MIMO) technology is gradually developed. A MIMO system is a core technology applied to the 802.11n. The 802.11n is a brand new wireless local area network technology of the Institute of Electrical and Electronics Engineers (IEEE) after the 802.11b\a\g. At the same time, a dedicated MIMO technology may improve performance of an existing 802.11a/b/g network. The MIMO technology is also currently used in a long term evolution (LTE) technology.
How to maximize a rate of a mobile terminal product in the LTE has always been an important index extremely focused by terminal device manufacturers and operators. When performing a performance comparison, an operator sometimes focuses on a peak rate of a terminal device.
In the prior art, a problem of a peak rate of a terminal device is considered and solved only from the perspective of efficiency of an antenna; however, the foregoing measure is limited, and there is an extremely great difficulty in an adjustment. For example, a rate is improved by optimizing efficiency of first and second antennas; however, great difficulty in debugging work of the antennas exists, and operational space for a terminal product is limited; and when performance of the first antenna is adjusted, another frequency band (that is, not a signal transmission frequency band on which an antenna performance adjustment is currently performed) of the first antenna is also greatly affected, as a result, it is very difficult to achieve a balance among frequency bands.